SV: [xml-dev] When to Validate XML?

["Jens Jakob Andersen, PDI" <jens.jakob.andersen@post.dk>]

Hi Mike

Well, yes, I got out in the "rest of the world", (for normal info, I
worked with Software AG as a Tamino product manager before coming to the
Danish Post, where I work as Enterprise IT Systems Architect), where
we're solving problems, not fighting for Native XML vs. RDBMS stoerd
XML. (I know of companies using Oracle and IBM MQ Series to handle all
their XML with no problems and quite good performance....)

In this "Why validate XML scenario", I guess that what I intended to
write was:

* XML Schema (DTD) can be used to validate structural constraints on the
XML Documents.
* Semantic validation of XML documents must be done in the application
(that is until i.e. RDF-S, DAML+OIL as well as easy to use inference
engines become widely available and easy to use;-))

You write:
>If so, is that because the DB triggers/rules/etc. have too much of a
performance burden?

This depends heavily on the RDBMS and the way it is designed. For e.g
Oracle I can say that I've never experienced any performance problems
with the systems I've worked with.

So it is not a performance issue, it is a "Semantic Issue". There are
not any systems (that I know of) yet, than can validate the Semantics of
your data, only the structure. But this is great, validating the
structure, and having some easy top use tools for this (your RDBMS or a
validating parser), is a must before you can validate the Semantics of
the documents.

And again, at the time being, I do not know of any easy to use and
configure systems/tools, (besides building it into the application
logic) that offers validation of the Semantics of a document.

I hope that this helps to clarify the issue I raised, by changing the
question of "When to Validate XML" over to "Why Validate XML, and what
do we want to achieve by doing so".

Best regards

Jens Jakob Andersen